Frequency and pattern of test utilization rate in clinical biochemistry laboratory: two different large hospital examples

Objectives: Clinical biochemistry laboratories (CBL) are the most frequently utilized laboratory group in healthcare, and their significance in patient care is indisputable. This study investigated the frequency and pattern of test utilization rate in CBL at two large hospitals’ outpatient and inpatient clinics. Methods: A total of 43,732,428 CBL tests, including clinical chemistry, immunoassay, coagulation, specific proteins, CBC, and urinalysis, were conducted for 12,182,382 patients across two large hospitals in different settings between 2018 and 2022. These tests were analyzed alongside patient admissions data, with a focus on the distribution across various clinics. Results: A total of 94 % and 93 % of those admitted to Hospitals 1 and 2 were outpatients. They had applied to CBL laboratories for 27.1–30.3 % of outpatients and 81.2–88.7 % of inpatients for at least one test. When analyzing the rates at which laboratory tests were requested for outpatients, it was found that emergency departments had the highest test-requesting rates, ranging from 19.99 to 45.36 %. This was followed by internal medicine clinics, with rates ranging from 13.77 to 14.8 %, and inpatient intensive care units, with rates between 24.31 and 30.14 %. Outpatients had 10–11 test requests for each patient and 16–31 for inpatients. The most frequently requested laboratory tests were CBC, glucose, creatinine, urea, AST and ALT in two hospitals. Conclusions: Despite significant variations in location, structure, medical staff, and patient demographics, approximately one-third of outpatients and 85 % of inpatients at these hospitals undergo testing in CBL. CBLs are essential for screening, diagnosis, prognosis, and healthcare treatment.